Estimating Gorgan's vulnerability to earthquakes with emphasis on the distance from infrastructure using fuzzy logic

Earthquakes have always affected human communities, leaving irreparable damage. Therefore, getting prepared to deal with such crisis through identifying vulnerable spots and eliminating them are effective strategies in reducing the damage caused by an earthquake. Many Iranian cities are located in the areas with medium or high relative risk of earthquake. The city of Gorgan with a population, over 330,000 and an area of 3600 hectares in 2012 one of the cities located on earthquake-prone zones with high relative risk of earthquake. Poor positioning of infrastructure plays major role in increasing the vulnerability of the cities during an earthquake. In this paper, the extent of vulnerability in Gorgan was considered through calculating, combining and analyzing factors such as access to medical centers, the distance from fire stations, access to temporary accommodation spaces and the distance from gas stations and gas pressure reduction sites using fuzzy logic model and Arc GIS software. Based on the final map, the distribution of infrastructures in Gorgan has not been accomplished well. The buildings in the western and southern parts of the city, including neighborhoods in the path of nahaarkhoran and Kashani Boulevard are more vulnerable compared to the other parts regarding the distance from infrastructures. This can be met by positioning urban facilities and urban equipment in the mentioned areas. Proper distribution of urban infrastructures in metropolitan areas of cities, including neighborhoods in the path Golshahr, belt road and Imam Reza road protects these areas from earthquakes so that they will suffer less destruction in the event of an earthquake.